Clamp for derricks



March 3, 1931.

J. D. MCEWEN 1,795,032

CLAMP FOR DERRICKS Filed April 30, 1927 2 Sheets-Sheet 1 WiTNESSES INVENTOR En WWW WM,M2@JW w. W

March 3, 1931. J. D. M EWEN CLAMP FOR DERRICKS Filed April 3b, 192? 2 Sheets -Sheet 2 INVENTOR WlTNESSES Patented Mar. 3, 1931 UNITED STATES PATENT OFFICE JOHN D. MCEWEN, PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO LEE 0. MOORE & COM- PANY, INCORPORATED, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA CLAMP non DERRICKS Application filed April 30,

This invention relates to clamps for tubular leg members of metal derricks, particularly those used for drilling and operating oil wells, and the like.

The objects of the invention are to improve the construction of such clamps. The improvements comprise better arrangement and construction of parts giving greater strength without increase of weight and greater convenience in fabrication and application.

Referrin to the drawings, Fig. 1 is a plan View of a clamp as applied to the top of a tubular leg section; Fig. 2 is a section of the clamp only on the line II-II of Fig. 1; and Fig. 3 is a perspective view of the clamp as applied to adjoining tubular sections, with other portions of the derrick structure indicated as applied thereto.

As is well known in this art, all-metal derricks for oil well drilling and the like, are largely employed. They usually consist of four corner columns or legs, formed by end to end coaxial tubes, theadjoining ends of the tube sections being connected together by clamps, and the corner columns being connectedto each other by cross girts and braces, for the purpose of forming the whole into a strong selfsupporting structure.

Such derricks are well known in this art, and therefore no general illustration or description thereof is necessary to an understanding of this invention by those skilled in the art.

Referring to'Fig. 3, a clamp is illustrated as applied to adjoining tubular leg sections 1 and 2, with diagonal braces 3 and 4:, and a horizontal girt 5 attached as in the completed derrick.

The clamp comprising the present invention is made of a single piece of plate metal, forged to final shape by suitable punching, die, and pressing operations. When completed the clamp C is bent to circular form, the diameter of the inside of the clamp being slightly larger than the external diameters of the leg sections 1 and 2 that are to be connected by the clamp. The edges of the clamp are turned outward to form flanges and 11, as indicated in Fig. 1'. These are not normal- 1927. Serial No. 183,026.

ly in contact with each other, having a gap between, so that compression bolts 12a may be applied to these flanges to constrict the clamp, whereby to draw the clamp tightly into contact with the ends of the tubular section when positioned therein as indicated in Fig. 3, so as to rigidly and permanently engage them under normal conditions.

From the main body portion of the clamp upper cars 12, intermediate ears 13, and lower ears 14, are struck up, on each side of the clamp. These ears or flanges have suitable perforations 15 for receiving bolts 16 adapted to pass therethrough and through the ends of the respective connecting girts and braces 3, 4 and 5, as indicated in Fig. 3.

Adjoining ends of tubular sections 1 and 2 are each adapted to extend to the median transverse plane of the clamp, and to abut end to end in the line of that plane, as indicated in Fig. 3. Positioned above and below the me dian plane, respectively, are diametrically oppositely positioned pairs of bolt holes 20, 20, and 21, 21, respectively. These are adapted to receive transverse bolts 23 and 22, respectively, which are adapted to extend through the walls of the clamp, and through the walls of the adjacent tubular sections respectively, near their ends, as shown in Fig. 3. These bolts furnish a positive lock of the tubular sections in the clamp, as will be apparent. They also reinforce the gripping action of the clamp upon the tubular sections, and furnish a safe-guard against the pulling out of the tubular sections, due to wind strains, or other causes. The perforations 20, 20, and 21, 21 are positioned at points where they will least weaken the body structure of the clamp.

The ears 12, 13, and 14 are in two similar sets, those of each set lying in a common diametrical plane. The two sets of ears are struck up from the plate from portions thereof unsymmetrically positioned with respect to the edge flanges 10 and 11. One set of ears, shown at the lower corner of Fig. 1, is struck up from metal near terminal flange 10, while the other set of ears is struck up from metal diametrically opposite and comparatively more remote from edge flange 11. As a reand the tubular sections, since the clamp may be placed upon the upper free end of a lower tubular section 1, and the lower bolt 22 put through the holes 21, 21 and through corre: sponding holes in the upper end of the tubularsection 1, thus servingpreliminarily. to position and holdthe clamp in place while the otherv tubular section 2 is being brought into position. This is oi great convenience, since it permits aready preliminary positioning and holding of theclamp upon the end of the onetubular section, without the necessity of tightening the bolts 12a. VVhereit is necessary to tighten these bolts in order tohold the clampin position-upon the first tube sectien that necessarily renders it somewhat diff cult to insert the other tubular section of the leg inthe Glampandto lower it to final positiontherein. V 1

ltwillbe further-observed that the bolts 22 and 23 seat atboth ends upon the body of the elamp,;that they not only positively lock the endsv of thetubular sections in the clamp, but they serve to squeeze the walls of the clamp together, andthus reinforceand addto-the constricting effect of the bolts 12a. Thecla-mp has advantages of structure that will beapparent to those familiar with this art.

-. cla m .1. In the art of metal derricks for oil well drilling and the like a clamp for connecting adjacent aligned sections of tubular derrick legs comprisinga single metal plate bent to c rcular-form wlth the meeting edges turned out to form substantially'parallel flange-s extending longitudinallythe full length of the. clamp, saidflanges being perforated to receive compression 7 boltswhereby to constrict the cl-amp to grip the ends'of tubes inserted;therein, .and perforated ears struck upQfromthe body of the plate and positioned foriattachment to girts and braces of a derrick structure, the clamp having oppositely disposed. perforations on each side of a median transverse plane positioned and adapted-to receive transverse diametric bolts extending through the. two walls of the clamp andthr-oughthe ends of adjoining tube sections, whereby to attach the clamp to each of theadjoining tubesections and to rigidly connect them to each other, said ears being so positioned that a-diametrical plane therebetween-will notcoincide with a diametrical plane between saidflanges, whereby to pro the clamp consisting of a metal plate bcntto circular term slightly larger in diameter than the tubular sections and having its longitudinal edges turned outward to form spaced apart substantially parallel flanges having perforations adapted'to receive compression boltswhereby to constrict the clamp to grip the tubular section ends, two sets of ears struck up from the body of the clamp remote from the edges thereof and positionedsubstantially at right angles to each other, the ears being perforated to receive bolts whereby to attach the usual. girts and braces of derrick structures, the clamp having perforations diametrically oppositely disposed in pairs respectively above and belowit-s median transverse plane and adapted to receive bolts passing through the .ends osf-the tubular sections held by the clamp, the ears being unsymmetricallypositioned with respect to the flanges, whereby to provide maximum room for the said through bolt holes.

3. A clamp for tubular leg. sections of welldrilling derricks iormedfr'om a single plate bent to cylindrical shape with terminal outward flanges opposed and perforated to provide means for compressingthe clamp on the tubular sections, and two sets of intermediate ears struck up from the body of the plate leaving openings betweenthe ears and said flanges and perforated toreceive bolts vfor ears .and.immediatelyfadjacent the bases of the firstmenti'onedset Qtears being perfo rated to. receive through bolts adapted to pass diametrically through the clamp and leg sections enclosed therein.

In testimony whereof, l sign myname.

' [JOHN ,DlVIoEWEN. 

